In general, monocrystalline silicon grown by Czochralski process (CZ process) includes thermal donors derived from interstitial oxygen. The thermal donors are generated depending on a thermal hysteresis experienced by the monocrystalline silicon when the monocrystalline silicon is pulled up, where it is known that the thermal donors are generated on a section of a straight body near an upper end thereof but are not generated on a section of the straight body near a lower end thereof. When there are thermal donors in the monocrystalline silicon used for a target material of sputtering or a plasma etching electrode, the resistivity of the monocrystalline silicon during the sputtering or plasma etching process becomes different from a target resistance value.
In order to restrain the above disadvantage, a donor-killer heat treatment, in which a region with the thermal donors is held at a temperature of 650 degrees C. or more for a predetermined time, is typically applied.
However, since the donor-killer heat treatment may sometimes result in a slip dislocation, a method without applying the donor-killer heat treatment has also been studied. For instance, Patent Literature 1 (JP 2015-40142 A) discloses a manufacturing method of a monocrystalline silicon used for a target material and the like, in which the resistivity of a section of 5-50 mm thick cut out from the monocrystalline silicon can be controlled to be within a range of a target resistivity ±10% without applying the donor-killer heat treatment by pulling up a monocrystalline silicon whose resistivity ranges from 10 Ω·cm to 50 Ω·cm.
However, according to the method disclosed in Patent Literature 1, it is possible that the resistivity cannot be controlled to be within the range of 10 Ω·cm to 50 Ω·cm due to the thermal hysteresis experienced by the monocrystalline silicon when the monocrystalline silicon is pulled up or uneven oxygen concentration of the monocrystalline silicon, so that the resistivity during the sputtering or plasma etching process may become different from the target value and desired sputtering and the like may be unable to be performed.